Hey guys,

 

I'm having a big problem with my Z. I'm pretty sure it's PTU related.

 

Basically, when driving the engine will start to act all weird, but only if i've been driving a while (long trips etc) or on very hot days.

 

The accelerator will go digital, so that it is either fully on, or fully off but the accelerator isn't pushed down all the way.

 

So, I pull over and it runs like shit. Turn the engine off and it won't start. Leave it for 10-15 minutes and it starts up and acts like nothing had ever been wrong? This will usually happen once on a long journey etc.

 

Anyway, with the recent hot weather it's happened after the car has been left out in the sun (no shade on my work car park :() engine started briefly, but ran like shit. Sounded like it was on 5 cylinders or something. After i've restarted it, I will not start. The starter runs, but there is no ignition. Also, it sounds like the fuel pump or hicas (it is at the back of the car?) constantly runs until I disconnect the battery. This also has happened the previous times.

 

I am pretty sure that when I return to the car this evening or early tomorrow morning it will start again like nothing happened.

 

Now it sounds a lot like a PTU issue, but I replaced the PTU about a year ago. (I didn't replace the loom...). The PTU I bought was second hand though, but it was series 2.

 

Any ideas?

yep ptu in my old opinion.

buy a new 1 bud

Just as an update - returned to the car and started without any issues.

 

Bah.

Sounds like classic PTU failure to me too. Get it replaced with a series 2 one and it shouldn't happen again mate.

if no one on here has one............

 

from the USA...

 

http://www.courtesyparts.com/22020-power-transistor-unit-ptu-harness-1989-1999-300zx-z32-p-182593.html

 

or

 

http://www.z1motorsports.com/advanced_search_result.php?search_in_keywords=1&plural=1&s=1&sort=3a&keywords=ptu

Sounds like classic PTU failure to me too. Get it replaced with a series 2 one and it shouldn't happen again mate.

 

he already replaced it with a series 2 one, and still getting these issues

has he done all the usual checks .... connector corrosion, MAF, coil packs, injectors, vac leak.. etc?

 

Conzult (or other diags)...

he already replaced it with a series 2 one, and still getting these issues

 

good spot, didn't read that bit :blush:

I have a Series 2, going spare if the OP's interested?

Might be worth checking the fuel pump relay,

sounds like it sometimes stays in contact and maybe sometimes not at all.

Just a thought.

If it is a second hand PTU, then maybe it could be fried. A new series II PTU is the only way to eradicate any issues relating to a faulty PTU.

 

Alz.

second hand ptu.....id of bought new .i dont no if series2 ptu's are known to die tho

Series 2 ptu's don't suffer with the heat problem... they are the upgrade due to that problem...

 

I would look for another problem first... if really worried, then borrow a ptu to check.

 

 

do all the usual checks .... connector corrosion, MAF, coil packs, injectors, vac leak.. etc?

 

Conzult (or other diags)...